Developments in biologicals最新文献

Germany has reported one of the highest levels of EBLV cases in bats in Europe. So far, all isolates originating from Germany have been identified as EBLV-1, using monoclonal antibodies, and a preliminary epidemiological study has indicated that there is a distinct geographical distribution of EBLV-1 in Germany. To further investigate the spatial and temporal distribution of EBLV-1 variants in Germany and their impact on molecular epidemiology, isolates were selected using a random grid sampling procedure based on GIS. Agrid layer 30 km long over the entire area of Germany was applied to 120 geo-referenced isolates and one isolate of each grid cell containing EBLV isolates was randomly chosen. Once selected, the nucleoprotein (N) plus parts of the phosphoprotein (P) gene of each isolate were sequenced using direct cycle sequencing. Results of the subsequent phylogenetic analysis of the N-gene confirmed previous studies on European EBLVs, showing a high sequence homology between German EBLV-1 isolates. Almost identical sequence homologies within certain geographical regions indicate genomic stability during the transmission cycle of EBLV-1, with little geographic spread or intermixing. Interestingly, a 6 bp insertion as well as a single nucleotide insertion, detected in the N-P intergenic region, has been found in EBLV-1 isolates from Germany.

Biomedical research utilizes animal models to elucidate human disease processes at the cellular and molecular level and for the development of new therapies. Traditionally, mammalian models have been limited to the mouse, primarily because of well characterized genetic lines and the ability to manipulate the genome to directly test hypotheses regarding causal mutations and disease phenotypes. The emerging availability of genome sequences of other mammals (bovine, canine, equine, feline, and porcine) now permits utilization of the mammal in which the phenotype best approximates the human condition. Equally important is the use of somatic cell nuclear cloning (SCNT) coupled with targeted germline manipulation to create animals to resolve the molecular mechanisms of the disease state. Our efforts have focused on the pig, which has emerged as an important biomedical mammalian model due to its closer physiology to humans. The utility of porcine genetically-defined tumour, cardiovascular and neurological disease models is described.

The modern version of epigenetics includes the molecular mechanisms that influence the phenotypic outcome of a gene or genome, in absence of changes to the underlying DNA sequence. A host of genomic interrelationships with the diet evidently exist. The broad topic of nutrigenomics is defined as the interaction between nutrition and an individual's genome. Ruminant species have evolved to metabolize the short-chain volatile fatty acids (VFAs, acetate, propionate, and butyrate) to fulfill up to 70% of their nutrient energy requirements. The potential biological roles of VFAs were investigated using the established Madin-Darby bovine kidney epithelial cell line. Butyrate induces cell cycle arrest and apoptosis in bovine cells. Gene expression profiling indicated that butyrate induces many significant changes in the expression of genes associated with regulatory pathways that are critical to cell growth, immune response and signal transduction. Functional category and pathway analyses of the microarray data revealed that several canonical pathways (the cell cycle G2/M DNA damage checkpoint and G1/S checkpoint regulation; pyrimidine metabolism; and purine metabolism insulin-like growth factor axis components) were significantly affected.

Toll-like receptor-2 (TLR2) and caspase recruitmentdomain 15 (CARD15) are important pattern recognition receptors that play a role in the initiation of the inflammatory and subsequent immune response. They have been previously identified as susceptibility loci for inflammatory bowel diseases in humans and are, therefore, suitable candidate genes for inflammatory disease resistance in cattle. The objective of this study was to identify single nucleotide polymorphisms (SNPs) in the bovine TLR2 and CARD15 and evaluate the association of these SNPs with health and production traits in a population of Canadian Holstein bulls. A selective DNA pool was constructed based on the estimated breeding values (EBVs) for somatic cell score (SCS). Gene segments were amplified from this pool in PCR reactions and the amplicons sequenced to reveal polymorphisms. A total of four SNPs, including one in intron 10 (c.2886-14A>G) and three in exon 12 (c.3020A>T, c.4500A>C and c.4950C>T)were identified in CARD15; nonewere identified in TLR2. Canadian Holstein bulls (n=338) were genotyped and haplotypes were reconstructed. Two SNPs, c.3020A>T and c.4500A>C, were associated with EBVs for health and production traits. The SNP, c.3020A>T for example, was associated with SCS EBVs (p = 0.0097) with an allele substitution effect of 0.07 score. When compared to the most frequent haplotype Hap12(AC), Hap22(TC) was associated with increased milk (p < 0.0001) and protein (p = 0.0007) yield EBVs, and hap21(TA) was significantly associated with increased SCS EBV (p = 0.0120). All significant comparison-wise associations retained significance at 8% experimental-wise level by permutation test. The role of SNP c.3020A>T in MDP induced IL-1beta expression was investigated by real-time quantitative reverse transcription-PCR (real-time quantitative RT-PCR). The induction of IL-1beta by MDP was highly variable between individuals, and no association was observed between IL-1beta expression and SNP c.3020A>T genotypes. In summary, the association study indicates that SNP c.3020A>T might play a role in the host response against mastitis; however, it is not the sole determinant of MDP induced IL-1beta expression in blood leukocytes. Further detailed studies are needed to understand the functional implications of SNP c.3020A>T.

The transcriptional profiles of chicken macrophages (HD11) infected with Salmonella enterica serovar Enteritidis (SE) were analyzed by using an avian macrophage microarray and real time RT-PCR. Out of 4906 array elements interrogated, 269 genes exhibited a 2 fold change (P < 0.001) over a 24 h time-course. Genes coding for proinflammatory cytokines, CC and CXC chemokines, and chemokine ligand were upregulated; whereas genes associated with transcription, cell adhesion and proliferation were downregulated. Most transcriptional changes occurred at 5 hours post-inoculation (hpi), with more genes downregulated than upregulated.At 5 hpi, the levels of gallinacin 1, lymphotactin, RhoA, and MHCIB2M transcripts were significantly decreased. In contrast, the levels of Cdc42 and MHCIIBLB2 mRNA were elevated. Infection of HD11 cells with mutant SE strains carrying an inactivated type three secretion system (TTSS1 or TTSS2) induced significantly higher levels of CCL4, K203, lymphotactin, and RhoA than wild type SE. In conclusion, chicken macrophage genes belonging to diverse functional classes were transcriptionally modulated by SE and selective modulation of host innate responses involved the effectors of TTSS1/2.

A Monoclonal antibody (MAb)-based capture enzyme-linked immunosorbent assay (ELISA) named WELYSSA was developed for the diagnosis of rabies suspected specimens using prototype viruses from the different genotypes of lyssavirus and from various geographic origins and phylogenetic lineages. It included a panel of 1,660 specimens received for rabies diagnostic testing, and was found to be highly specific (99.9%) and sensitive (97.0%) when compared to other recommended rabies diagnostic methods.

The first International Symposium on Animal Genomics for Animal Health, held at the World Organisation for Animal Health (OIE) Headquarter, 23-25 October, 2007, Paris, France, assembled more than 250 participants representing research organizations from 26 countries. The symposium included a roundtable discussion on critical needs, challenges and opportunities, and a forward look at the potential applications of animal genomics in animal health research. The aim of the roundtable discussion was to foster a dialogue between scientists working at the cutting edge of animal genomics research and animal health scientists. In an effort to broaden the perspective of the roundtable discussion, the organizers set out four priority areas to advance the use of genome-enabled technologies in animal health research. Contributions were obtained through open discussions and a questionnaire distributed at the start of the symposium. This symposium report provides detailed summaries ofthe outcome ofthe roundtable discussion for each of the four priority areas. For each priority, the problems needing to be solved, according to the views of the participants, are identified, including potential solutions, recommendations, and lastly, concrete steps that could be taken to address these problems. This report serves as a roadmap to steer research priorities in animal genomics research.

Preventive vaccination against rabies virus is a highly effective method for preventing rabies in humans and animals. For travel purposes, vaccination of domestic carnivores is obligatory. In addition, some countries require testing for neutralizing antibodies against rabies. The minimal threshold level accepted by WHO/OIE is 0.5 IU/ml. Despite proper vaccination some animals do not reach the threshold. The objective of this study was to identify specific risk factors in dogs and cats for post-vaccination rabies antibody titres below 0.5 IU/ml by FAVN test. Rabies vaccination protocols and recommendations were reviewed with regard to travel regulations. Comprehensive data was collected on animals tested for rabies antibodies via a questionnaire sent to veterinarians who submitted sera for rabies titration. The questionnaire included data on species, age, sex, breed, vaccine used, date of last vaccination and blood sampling, vaccination history and further medical treatments at time of vaccination. Data on around 1,200 animals was analysed. Most animals older than one year had already received more than one rabies vaccination. The influence of breed and sex on antibody titre seems to be insignificant. Young dogs have a high risk of results below 0.5 IU/ml after their first vaccination. This risk can be minimised by the application of a second vaccination and blood sampling according to the manufacturer's recommendations. An important factor for the test outcome might be the virus strain used in the vaccine.

There have been many changes and accomplishments in rabies control and prevention since the first International conference "Rabies in Europe" was held in Kiev on June 15-18, 2005. Recommendations from the 2005 meeting addressed epidemiology; rabies diagnosis; animal rabies control; human rabies prevention; vaccinology and immunology and bat rabies. This paper will adhere to the same topics of interest in order to review the accomplishments that have been achieved since Kiev.